Fin Dorsal is a good low-rank boss. He drops his weapon, Fin's Cutters, and I believe he can drop a pet as well. Or, for good gear and possible pets, farm the Temple of Fire in Xol Akmul, or Emperor Prawn, or the Floating Dutchman!
Easy as in one battle in and out? Two I know of in MooShu, Abe Pagoda in Subata Temple, the boss there can drop the tawny sky turtle pet; which is one half of what you need to create the hybrid - paper dragon ( the other half is a celestial sky dragon ). Friar Sand has been known to drop a sky turtle mount, you can find him at the Corrupted Shrine.